Pressure pump



Feb. 8, 1949. l.1. M. SCHMIED 2,460,949

REssURE PUMP Filed Nov. 23, 1945 f 2 sheets-sheet 1 f Josejo j! Scmiec PRESSURE PUMP Filed Nov. 23, 1945 7 2 sheets-sheet z Bymm ' Patented Feb. 8, 1949 Joseph M. Schmied, Chicago, Ill. Application November 23, 1945, Serial No:630,'2l2

My invention relates to multicylinder pumps, and more particularly to pressure pumps oi the balanced type wherein one or more cylindrical bodies or piston barrels, are provided with a series of cylinders in which pistons are caused to reciprocate by means of a cam operatingon the ends of the pistons.

The principal object of my invention is to 5 claims. (ci. 10a-173) reference character A, and is formed by two identical halves indicated at I and- I2 held together by studs I4 and nuts I6, the studs being received by holes I8 in the abutting-flanges 20--20, as

provide a pump of this general character in which the pistons not only act topump-'a fluid under high pressure, but also serve as the valve means thus eliminating the usual valves-and materially reducing the number of parts necessary in the construction of the pump.

Another important object ofI my invention is i to provide a pressure pump of the above character which is double acting, and wherein two series of pistons are simultaneously reciprocated by a single c'am member so that bearing loads are substantially cancelled out.

Still another object of my invention is to construct a pressure pump wherein the pistons are returned by push pins acted upon by conned wobble plates, the construction being such that the pins are in constant engagement with the 1 wobble plates and the ends of the pistons are in and in which:

Fig. 1 is a centraislongitudinal section of my improved pump, parts appearing in elevation.

Fig. 2 is a cross-section through one side of the pump on a plane indicated by the line 2--2 of Fig. 1.,

Fig. 3 is a cross-section through the opposite side of the pump on' o-set planes indicated by the line 3-3 of Fig. 1 .looking in the direction of the arrows.

Fig. 4 is a developed view showingthe progressive action of one set or series of the pump pistons.

Fig.l 5 is a perspective view of one of the shoe plates used between the crowned end of the pistons and the driving cam, and

Fig. 6 is a perspective detail of. one of the piston barrels looking toward the transfer' conduits or passageways.

In the embodiment of my invention illustrated,

the pump casing is designated as a whole by the f..

.pressure pump embodying my said improvements clearly shown in Figs. 1 and 2. Half I0 of casing A is formed with a cylindrical bore. 22 to snugly receive the cylindrical piston body or barrel 24 and barrel end plate member 26, the latter being located between the body 24 and end wall 28 of casing half I0 as best shown in Fig. 1.

It will be further observed from Fig. 1 that piston barrel 24, barrel plate member 26 and end wall. 28 are centrally bored to receive a bushing 30, and end 32. oi the cam shaft B, while piston body 25, plate member 21 and end wall-29 of casing half |12, are similarly provided with a central bore to receive the bushing 3I and end 33 of the cam shaft B. Piston barrel 24 is supplied with,L a series of spaced horizontal through bores. or cylinders 35, within which a set of pistons 34 are reciprocated by face F of cam C in a manner presently disclosed. Cam C may be termed a driving inclined wobble plate. cylinders 35'are connected by conduits 36 formed in the body 24 with the exception of the uppermost cylinders (Fig. 4) located adjacent the outlet' port D and inlet portE formed in the casing half I 0. There is also provided shallow clearance grooves 38, in the plate member 26, which are in axial alignment with their respective cylinders and oi a diameter to receive the outer ends of pistons 34 when they pass beyond the conduits 36 in a manner and for reasons later explained in connection with the valve arrangement.' For each piston 34 there is a push pin 4I).l

of cam C. The outer., end of cylinders 31 areconnec'ted by transfer passageways or conduits 43, formed in the piston barrel 25 adjacent the barrel plate 21, with the exception of the uppermost cylinders located adjacent 'the outlet port4 D' and inlet port E' formed in the casing halfv I2. Shallow clearance grooves in plate member 21- are in axial alignment with their corresponding cylinders 3l and of adiameter suitable to receive the: outer ends of pistons 39 when they pass be- The outer end of yond the conduits 43. For each piston 33 there is a push pin 41, and these pins pass through aligned holes in the plate 21 and end wall 23 to contact the inner surface 43 of wobble plate Il. This wobble plate is also enclosed within a cap 53 secured to the end wall 23 by screws il. It will be noted from Fig. 1 that end 33 of cam shaft B passes through a hole in wobble plate 3i and an opening in cap 53 which is made leakproof by sealing means such as indicated at 54.

In Fig. 5 I have shown one of the sliding shoes l *used between each piston and the driving cam C. These shoes preferably comprise hardened disks 56, one face of which is at to slidably en-l ing movement relative to the cam and pistons.

Returning now to Fig. 4, wherein is shown a development of piston barrel 24, barrel plate 26, end wall 28, and the series of pistons 34, it will be observed that said pistons are given a wavelike motion by cam face F of cam C when the cam shaft B is rotated in the direction indicated by arrow Il. As shown in this view the highest rise of cam face F is between the pistons 34.1 and 34.1, and when in this position said pistons will have reached the end of their outward stroke to close the inlet port E and outlet port D respectively, and a complete filling of fluid between said pistons has taken place.

As the cam C is rotated further in the direction -indicated by arrow il (Fig. 4) the highest rise of cam face F leaves piston 34.1 and approaches piston 34.I. Thus piston 34.1 will begin its discharge stroke and simultaneously start to uncover discharge port D. Upon still further movement of the cam C, pistons 34.! to 34.1 will be progressively moved through a pressure stroke anda suction stroke. To state it another way, for each rotation` of the cam C, each piston of the series 34 and 39 will be moved through a pressure stroke and a suction stroke.

It will now be understood that when the lowest point of cam face F is between pistons 34.| and 34.1, piston 34.4 will be opposite the highest rise of cam F and at the end of its pressure stroke thus dividing the transfer conduits or passageways 36 midway the inlet and discharge ports E and D, and both of said ports will be open at this position of cam C. The pumping action of the series of pistons 39, brought about bythe cam face G of cam C is identical to that just.

described in connection with the series of pistons 34 acted upon by cam face F of cam C, and for this reason will'not be repeated. The pistons each successively close the transfer conduit for a time interval at the end of the piston pressure stroke to insure iiow from the inlet to the outlet port. Suilice it to say that when'piston 34.1 of the series 34 is opposite the low point of cam face F, piston 39.| of the series 39 is opposite the low point of cam face G, and that all other pistons of the two sets are in progressively complementary positions.

It is believed that operation of the push pins 40 and 41 for pistons 34--33 respectively will be apparent from a study of Fig. 1. As the pistons .4 l by the conventional and well known wobble plate action.

Mention has already' been made of' the fact that no valves are used in my improved pump aside from the pistons themselves. For an explanation of this novel valve arrangement attention is again directed to the developed view of Fig. 4 wherein it will be recalled the pistons 34.| and 34.1 are shown at the end of their outward stroke, ports E and D are closed, and the pump is completely filled. In other words, all of the transfer passages 38 are in communication with one another as shown in this ligure. Now as the cam C is rotated in the direction indicat- .ed by arrow li, the highest rise of cam face F will approach piston 34.2 causing it to move outwardly (Fig. 1) ordownwardly (Fig. 4) and when said highest rise of cam face F ls opposite said piston 34.2 its outer end will be seated in its associated clearance groove 38. Any oil trapped between the end of piston 34.2 and its clearance groove 38 will be discharged or permitted to escape through the notch-like cavity 38.| into the adjacent transfer conduit 3B on the pressure side of piston 34.2.

Similarly, when the highest rise of cam face F is opposite piston 34.3 its outer end will be seated in its associated clearance groove 38 and so on as the cam C is rotated. From this it follows that when piston 34.3 is seated in its clearance groove 38, in the barrel plate 26, pistons -34.1

and 34.1 will have commenced their inward travel to uncover the inlet port E and discharge port D respectively,` and that duid on the pressure side of piston 34.3 will be forced out the outlet port D while fluid on the suction side of said piston 34.3 will be drawn inl through the inlet port E. It will now be observedthat the pistons opposite the highest rise of the cam faces F and G of cam C will be the dividing point between the suction side and discharge side of the pump, and as the cam C continues to rotate, this dividing point progressively changes.

It has been found that due to this construction, extremely high pressures can be built up by the pumping action of the pistons, and since the pump is double acting, bearing loads are substantially balanced or cancelled out completely.

The improved multi-cylinder pump or compressor herein described besides being of an extremely compact and simple construction and capable of producing high pressures, has the important advantage that the working stresses are distributed evenly and at a large number of points which accounts for the smooth working andincreased useful life of the pump.

Still another and important advantage of my improved pump structure is found in the rcduction of pulsations in the delivery of the pumping fluid which in a great measure is brought about by the absence of separate valves and the novel valve arrangement disclosed herein.

While I have shown and described a particular embodiment of my invention, it will be readily understood by those skilled in the art that variations may be made in the construction disclosed without departing from the basic features of myk invention. I therefore do n'ot wish to .be limited to the precise construction disclosed, but wish to include within the scope of my invention all such modifications and variations which will readily suggest themselves.

What I claim asnew and desire to secure by Letters Patent of the United States is:

` 'amano 1. Ina multlcylinder pump, the combination of a casing having a cylindrical bore, arf-.cylinder inlet and outlet also passing ythrough the casing body and barrel plate fitting in the cylindrical -duit in the cylinder body connecting said cylinders, a partition between two adjacent cylindersn an inlet in communication with one of the two adjacent cylinders andI an outlet in communicationwlth the other' of the two adjacent cylinders, said inlet and outlet also passingthrough the casing wall, thereby providing inlet and out- `let ports clearance grooves`in said barrel plate in axial `alignment with said cylinders, a conflned wobble plate housed within said casing. a push pin for each piston mounted for reciprocable movement in aligned bores in the barrel plate and casing end wall, and acted upon by said wobble plate to move said pistons in one direction. a cam shaft rotatably mounted in the end wall of said casing, and a driving inclined wobble plate xed for rotation on said shaft and having its inclined face adjacent the ends of said pistons in parallel relationship with the plane ofthe confined wobble plate face so as to impart a progressive reciprocating motion to said pistons and their respectively associated push pins in a direction opposite to that impartedy to the pistons by said confined wobble plate, the pistons each successively closing Ythe transfer conduit for a time interval at the end of the plsinders, a transfer conduit in the cylinder body at one end thereof connecting said cylinders, a partition between two adjacent cylinders, an inlet in communication with one of the two adjacent cylinders and an outlet in communication with the other of the two adjacent cylindcrs,said in- `let and outlet also passing through the casing wall, thereby providing inlet and outlet ports clearance grooves at the ends of each cylinder extending beyond said transfer conduit, a confined wobble plate housed within said casing, a push pin for each piston-mounted for reciprothat imparted to the pistons by said wobble plate,

cable movement in the casing end wall and acted upon by said wobble plate to move said pistons in one direction, a cam shaft rotatably mounted in the end wall of said casing, -anda driving inclined wobble plate fixed for rotation on said shaft and having its inclined face adjacent the ends of said pistons in parallel relationship with the plane of the wobble plate face so as to impart a progressive reciprocating motion to said pistons and their respectively associated push pins in a direction opposite to that imparted to the pistons by said wobble plate, the pistons each successively closing the transfer conduit for a time interval at the end of the piston pressure stroke to insure ow from the inlet to the outlet port.

3. In a multicylinder pump, the combination of y wall, thereby providing inlet; and outlet ports clearance grooves at the ends of each cylinder extending beyond said transfer conduit, a fluid escape passage leading from each clearance groove, a confined wobble plate housed within said casing, a push pin for each piston mounted for reciprocable movement in the casing end wall and acted upon by said wobble plate to move said pistons in' yone direction, a cam shaft rotatably mounted inthe end wall of saidcasing. and a driving inclined wobblaplate .fixed for rotation on said shaft and having its inclined face adjacent the ends of said pistons in parallel relationship .with the plane of the wobble plate face so as to impart a progressive reciprocating' motion to said` pistons 4:and their respectively associated push pins in a directionoppositeto thev pistons each successively closing the transfer conduit for a time interval at the end of the piston pressure stroke to insure vilow from the inlet to the outlet port.

4. In a multicylinder pump, the combination of a casing having a cylinder body portion with cylinders-therein,r;reciprocable pistons in the cylinders, a transfer conduit in the cylinder body at one endv thereof connecting said cylinders, a partition between two adjacent cylinders, an inlet in communication with one of the vtwo adjacent cylinders and an outlet in communication with the other of the two adjacent cylinders, said inlet and outlet also passingthrough the casing wall, therebypreviding inlet and 'out- `let ports clearance groovesiatthe ends of each escape passage being in direct communication with said adjacent conduit, a confined wobble plate housed Within said casing, a, push pin for each piston mounted for reciprocable movement in the casing end wall and acted upon by said wobble plate to move said pistons in one direction, a cam shaft rotatably mounted in the end wall of Vsaid casing, and a driving inclined wobble plate fixed for rotation on said shaft and having its inclined face adjacent the ends of said pistons in parallel relationship with the plane of the wobble plate face -so as to impart a progressive reciprocating motion to said pistons and their respectively associated push pins in a direction opposite to that imparted to the plstons by said wobble plate, the pistons eachk succe'ssvely closing the transfer conduit for a time interval at the end of the piston pressure stroke to insure flow from the inlet to the outlet port.

5. In a multicylinder pump, the combination of a casing having a cylinder body portion with cylinders therein, reciprocable pistonsl in the cylinders, a transfer conduit in the cylinder body at one end thereof connecting said cylinders, a partition between two adjacent cylinders, an inlet in communication with one of the two adjacent cylinders and an outlet in communication with the other of the two adjacent cylinders, said inlet and outlet also passing through the casing wall, thereby providing inlet and outlet ports e clearance grooves at the ends of each cylinder extending beyond said transfer conduit, means located within said casing to actuate said pistons progressively in a progressive reciprocating motion to provide a suction stroke of said pistons, and means cooperatively associated with said first named means located within said cas- 7 ing progressively to actuate said pistons to Pro1-1- UNITED STATES PATENTS .vide a pressure stroke therefor, the pistons eac ame successively closing the transfer conduit for a Nzmllew G01? 1 Aprnfzlgsa time interval at the end of the piston pressure 2232984 Wamgdxl; Feb 25 1941 stroke to insure iiow from the inlet to the outlet 5 2861301 Parsons 16, 1942 P0- zvsnza wahlmark Apr. 17, 1945 JOSEPH M. SCHMIED.

FOREIGN PATENTS REFERENCES CITED Number country Date The following references are of record in them 521,901 France Mer. 17, 1921 iiie of this patent: 

